Study of the "Fast SCR" -like mechanism of H2-assisted SCR of NOx with ammonia over Ag/Al2O3

It is shown that Ag/Al2O3 is a unique catalytic system for H-2-assisted selective catalytic reduction of NOx by NH3 (NH3-SCR) with both Ag and alumina being necessary components of the catalyst. The ability of Ag/Al2O3 and pure Al2O3 to catalyse SCR of mixtures of NO and NO2 by ammonia is demonstrated, the surface species occurring discussed, and a "Fast SCR"-like mechanism of the process is proposed. The possibility of catalyst surface blocking by adsorbed NOx and the influence of hydrogen on desorption of NOx were evaluated by FTIR and OFT calculations

Using motivational interviewing to improve self-efficacy : a literature review

Bakgrund Ohälsosamma levnadsvanor och livsstilsrelaterade sjukdomar är ett utbrett och växande problem i stora delar av världen. Motiverande samtal (MI) är en behandlingsform som visat sig effektiv för att hjälpa patienter få en bättre förståelse för faktorer som påverkar deras hälsa och stärka deras självtillit. Syfte Studiens syfte är att beskriva sjuksköterskans motiverande samtal som verktyg för att stärka patientens självtillit. Metod Metoden som har använts för denna studie är en strukturerad litteraturstudie med inslag av den metodologi som används vid systematiska översikter. Författarna har analyserat resultat från femton artiklar med bred geografisk spridning som berör användningen av motiverande samtal för att stärka patienters självtillit. Resultat Analysen av artiklarna visade två huvudteman - Fördelar med MI och hinder för att använda MI. Bland fördelarna listas det breda användningsområdet för metoden, att vården blir personcentrerad och framgångarna med att stärka patienters självtillit. De största hindren för MI listas som tidsbrist och bristfällig utbildning inom MI. Slutsats Motiverande samtal har visat sig ha god effekt inom en rad olika områden och har hjälpt till att stärka patienters självtillit. Värdet av den ökade självtilliten sträcker sig bortom den enskilda patienten och kan anses stärka folkhälsan vilket i förlängningen minskar belastningen på vården i sin helhet.Background Unhealthy lifestyle choices and lifestyle-related diseases are a widespread and growing problem in large parts of the world. Motivational interviewing (MI) is a treatment method that has proven to be effective in helping patients gain a better understanding of factors that affect their health and strengthen their self-efficacy. Aim The aim of this study is to describe the use of motivational interviewing to improve self-efficacy. Method The method used for this study is a structured literature study with elements of the methodology used in systematic reviews. The authors have analysed the results from fifteen articles with a wide geographical distribution that focuses on the use of motivational interviewing to improve self-efficacy. Results The analysis of the articles revealed two main themes – Advantages with MI and Barriers to using MI. Among the advantages are listed the wide range of use for the method, that care becomes more person-centered and the successes in improving patient's self-efficacy. The biggest barriers to MI are listed as lack of time and inadequate training in MI. Conclusions Motivational interviewing has been shown to have a good effect in a number of different areas and have helped to improve patient's self-efficacy. The value of the increased self-efficacy extends beyond the individual patient and can be considered to strengthen the public health, which in the long term reduces the burden on the healthcare system as a whole

Using motivational interviewing to improve self-efficacy : a literature review

Bakgrund Ohälsosamma levnadsvanor och livsstilsrelaterade sjukdomar är ett utbrett och växande problem i stora delar av världen. Motiverande samtal (MI) är en behandlingsform som visat sig effektiv för att hjälpa patienter få en bättre förståelse för faktorer som påverkar deras hälsa och stärka deras självtillit. Syfte Studiens syfte är att beskriva sjuksköterskans motiverande samtal som verktyg för att stärka patientens självtillit. Metod Metoden som har använts för denna studie är en strukturerad litteraturstudie med inslag av den metodologi som används vid systematiska översikter. Författarna har analyserat resultat från femton artiklar med bred geografisk spridning som berör användningen av motiverande samtal för att stärka patienters självtillit. Resultat Analysen av artiklarna visade två huvudteman - Fördelar med MI och hinder för att använda MI. Bland fördelarna listas det breda användningsområdet för metoden, att vården blir personcentrerad och framgångarna med att stärka patienters självtillit. De största hindren för MI listas som tidsbrist och bristfällig utbildning inom MI. Slutsats Motiverande samtal har visat sig ha god effekt inom en rad olika områden och har hjälpt till att stärka patienters självtillit. Värdet av den ökade självtilliten sträcker sig bortom den enskilda patienten och kan anses stärka folkhälsan vilket i förlängningen minskar belastningen på vården i sin helhet.Background Unhealthy lifestyle choices and lifestyle-related diseases are a widespread and growing problem in large parts of the world. Motivational interviewing (MI) is a treatment method that has proven to be effective in helping patients gain a better understanding of factors that affect their health and strengthen their self-efficacy. Aim The aim of this study is to describe the use of motivational interviewing to improve self-efficacy. Method The method used for this study is a structured literature study with elements of the methodology used in systematic reviews. The authors have analysed the results from fifteen articles with a wide geographical distribution that focuses on the use of motivational interviewing to improve self-efficacy. Results The analysis of the articles revealed two main themes – Advantages with MI and Barriers to using MI. Among the advantages are listed the wide range of use for the method, that care becomes more person-centered and the successes in improving patient's self-efficacy. The biggest barriers to MI are listed as lack of time and inadequate training in MI. Conclusions Motivational interviewing has been shown to have a good effect in a number of different areas and have helped to improve patient's self-efficacy. The value of the increased self-efficacy extends beyond the individual patient and can be considered to strengthen the public health, which in the long term reduces the burden on the healthcare system as a whole

The effect of gas composition on hydrogen assisted NH3-SCR over Ag/Al2O3

In addition to high activity in hydrocarbon-SCR, Ag/Al2O3 catalysts show excellent activity for NOx reduction for H2-assisted NH3-SCR already at 200 °C. Here, we study the influence of different gas compositions on the activity of a pre-sulfated 6 wt% Ag/Al2O3 catalyst for NOx reduction, and oxidation of NO and NH3. The catalyst displays high initial activity for NOx reduction with a maximum of about 85% at 250 °C. Increasing the concentration of H2 results in further increased NOx reduction. Moreover, a global stoichiometry between NO: NH3: H2 equal to 1: 1: 2 is established during selective NOx reduction conditions. When increasing the concentration of one of the reducing agents only an increase of the H2 concentration leads to an increase in NOx reduction, while an increase of the NH3 concentration only is beneficial to a limit of an equimolar ratio between of NO and NH3. Under transient conditions at constant temperature, the concentration of NO reaches steady state fast, whereas it takes longer time for NH3 due to accumulated surface species, probably on the alumina. The oxidation of NO to NO2 is sensitive to the H2 concentration in similarity to the SCR reaction, while higher amounts of H2 suppress the oxidation of NH3. Moreover, the dependency on the O2 concentration is much higher for the NO and NH3 oxidation than for the SCR reaction. To explain all these features a reaction mechanism is proposed in which the role of H2 is to free silver from single oxygen atoms. Ammonia and nitric oxygen can adsorb on these sites and react probably on the border between the silver and alumina or on the alumina surface to N2

The structure-function relationship for alumina supported platinum during the formation of ammonia from nitrogen oxide and hydrogen in the presence of oxygen

We study the structure-function relationship of alumina supported platinum during the formation of ammonia from nitrogen oxide and dihydrogen by employing in situ X-ray absorption and Fourier transform infrared spectroscopy. Particular focus has been directed towards the effect of oxygen on the reaction as a model system for emerging technologies for passive selective catalytic reduction of nitrogen oxides. The suppressed formation of ammonia observed as the feed becomes net-oxidizing is accompanied by a considerable increase in the oxidation state of platinum as well as the formation of surface nitrates and the loss of NH-containing surface species. In the presence of (excess) oxygen, the ammonia formation is proposed to be limited by weak interaction between nitrogen oxide and the oxidized platinum surface. This leads to a slow dissociation rate of nitrogen oxide and thus low abundance of the atomic nitrogen surface species that can react with the adsorbed hydrogen species. In this case the consumption of hydrogen through the competing water formation reaction and decomposition/oxidation of ammonia are of less importance for the net ammonia formation

The effect of the gas composition on hydrogen-assisted NH3-SCR over Ag/Al2O3

In addition to high activity in hydrocarbon-SCR, Ag/Al2O3 catalysts show excellent activity for NOx reduction for H2-assisted NH3-SCR already at 200 \ub0C. Here, we study the influence of different gas compositions on the activity of a pre-sulfated 6 wt% Ag/Al2O3 catalyst for NOx reduction, and oxidation of NO and NH3. The catalyst displays high initial activity for NOx reduction with a maximum of about 85% at 250 \ub0C. Increasing the concentration of H2 results in further increased NOx reduction. Moreover, a global stoichiometry between NO: NH3: H2 equal to 1: 1: 2 is established during selective NOx reduction conditions. When increasing the concentration of one of the reducing agents only an increase of the H2 concentration leads to an increase in NOx reduction, while an increase of the NH3 concentration only is beneficial to a limit of an equimolar ratio between of NO and NH3. Under transient conditions at constant temperature, the concentration of NO reaches steady state fast, whereas it takes longer time for NH3 due to accumulated surface species, probably on the alumina. The oxidation of NO to NO2 is sensitive to the H2 concentration in similarity to the SCR reaction, while higher amounts of H2 suppress the oxidation of NH3. Moreover, the dependency on the O2 concentration is much higher for the NO and NH3 oxidation than for the SCR reaction. To explain all these features a reaction mechanism is proposed in which the role of H2 is to free silver from single oxygen atoms. Ammonia and nitric oxygen can adsorb on these sites and react probably on the border between the silver and alumina or on the alumina surface to N2